491259666 has 32 divisors (see below), whose sum is σ = 1015492608. Its totient is φ = 158271120.

The previous prime is 491259607. The next prime is 491259673. The reversal of 491259666 is 666952194.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 241345 + ... + 243371.

It is an arithmetic number, because the mean of its divisors is an integer number (31734144).

Almost surely, 2^491259666 is an apocalyptic number.

491259666 is an abundant number, since it is smaller than the sum of its proper divisors (524232942).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

491259666 is a wasteful number, since it uses less digits than its factorization.

491259666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3366.

The product of its digits is 699840, while the sum is 48.

The square root of 491259666 is about 22164.3783129597. The cubic root of 491259666 is about 789.0485078310.

The spelling of 491259666 in words is "four hundred ninety-one million, two hundred fifty-nine thousand, six hundred sixty-six".